cli

FFmpeg Command Line

Cut video file into a smaller clip

You can use the time offset parameter (-ss) to specify the start time stamp in HH:MM:SS.ms format while the -t parameter is for specifying the actual duration of the clip in seconds.

ffmpeg -i input.mp4 -ss 00:00:50.0 -codec copy -t 20 output.mp4

Split a video into multiple parts

If you want to split a large video into multiple smaller clips without re-encoding, ffmpeg can help. This command will split the source video into 2 parts – one ending at 50s from the start and the other beginning at 50s and ending at the end of the input video.

ffmpeg -i video.mp4 -t 00:00:50 -c copy small-1.mp4 -ss 00:00:50 -codec copy small-2.mp4

Convert video from one format to another

You can use the -vcodec parameter to specify the encoding format to be used for the output video. Encoding a video takes time but you can speed up the process by forcing a preset though it would degrade the quality of the output video.

ffmpeg -i youtube.flv -c:v libx264 filename.mp4

ffmpeg -i video.wmv -c:v libx264 -preset ultrafast video.mp4

Join (concatenate) video files

If you have multiple audio or video files encoded with the same codecs, you can join them into a single file using FFmpeg. Create a input file with a list of all source files that you wish to concatenate and then run this command.

ffmpeg -f concat -i file-list.txt -c copy output.mp4

Mute a video (Remove the audio component)

Use the -an parameter to disable the audio portion of a video stream.

ffmpeg -i video.mp4 -an mute-video.mp4

Extract the audio from video

The -vn switch extracts the audio portion from a video and we are using the -ab switch to save the audio as a 256kbps MP3 audio file.

ffmpeg -i video.mp4 -vn -ab 256 audio.mp3

Convert a video into animated GIF

FFmpeg is an excellent tool for converting videos into animated GIFs and the quality isn’t bad either. Use the scale filter to specify the width of the GIF, the -t parameter specific the duration while -r specifies the frame rate (fps).

ffmpeg -i video.mp4 -vf scale=500:-1 -t 10 -r 10 image.gif

Extract image frames from a video

This command will extract the video frame at the 15s mark and saves it as a 800px wide JPEG image. You can also use the -s switch (like -s 400×300) to specify the exact dimensions of the image file though it will probably create a stretched image if the image size doesn’t follow the aspect ratio of the original video file.

ffmpeg -ss 00:00:15 -i video.mp4 -vf scale=800:-1 -vframes 1 image.jpg

ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%3d.jpeg

This will extract one video frame per second from the video and will output them in files named foo-001.jpeg, foo-002.jpeg. Images will be rescaled to fit the new WxH values

Convert Video into Images

You can use FFmpeg to automatically extract image frames from a video every ‘n’ seconds and the images are saved in a sequence. This command saves image frame after every 4 seconds.

ffmpeg -i movie.mp4 -r 0.25 frames_%04d.png

Merge an audio and video file

You can also specify the -shortest switch to finish the encoding when the shortest clip ends.

ffmpeg -i video.mp4 -i audio.mp3 -c:v copy -c:a aac -strict experimental output.mp4

ffmpeg -i video.mp4 -i audio.mp3 -c:v copy -c:a aac -strict experimental -shortest output.mp4

Resize a video

Use the size (-s) switch with ffmpeg to resize a video while maintaining the aspect ratio.

ffmpeg -i input.mp4 -s 480x320 -c:a copy output.mp4

Create video slideshow from images

This command creates a video slideshow using a series of images that are named as img001.png, img002.png, etc. Each image will have a duration of 5 seconds (-r 1/5).

ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -r 30 -pix_fmt yuv420p slideshow.mp4

Add a poster image to audio

You can add a cover image to an audio file and the length of the output video will be the same as that of the input audio stream. This may come handy for uploading MP3s to YouTube.

ffmpeg -loop 1 -i image.jpg -i audio.mp3 -c:v libx264 -c:a aac -strict experimental -b:a 192k -shortest output.mp4

Convert a single image into a video

Use the -t parameter to specify the duration of the video.

ffmpeg -loop 1 -i image.png -c:v libx264 -t 30 -pix_fmt yuv420p video.mp4

Add subtitles to a movie

This will take the subtitles from the .srt file. FFmpeg can decode most common subtitle formats.

ffmpeg -i movie.mp4 -i subtitles.srt -map 0 -map 1 -c copy -c:v libx264 -crf 23 -preset veryfast output.mkv

Crop an audio file

This will create a 30 second audio file starting at 90 seconds from the original audio file without transcoding.

ffmpeg -ss 00:01:30 -t 30 -acodec copy -i inputfile.mp3 outputfile.mp3

Change the audio volume

You can use the volume filter to alter the volume of a media file using FFmpeg. This command will half the volume of the audio file.

ffmpeg -i input.wav -af 'volume=0.5' output.wav

Rotate a video

This command will rotate a video clip 90° clockwise. You can set transpose to 2 to rotate the video 90° anti-clockwise.

ffmpeg -i input.mp4 -filter:v 'transpose=1' rotated-video.mp4

This will rotate the video 180° counter-clockwise.

ffmpeg -i input.mp4 -filter:v 'transpose=2,transpose=2' rotated-video.mp4

Speed up or Slow down the video

You can change the speed of your video using the setpts (set presentation time stamp) filter of FFmpeg. This command will make the video 8x (1/8) faster or use setpts=4*PTS to make the video 4x slower.

ffmpeg -i input.mp4 -filter:v "setpts=0.125*PTS" output.mp4

Speed up or Slow down the audio

For changing the speed of audio, use the atempo audio filter. This command will double the speed of audio. You can use any value between 0.5 and 2.0 for audio.

ffmpeg -i input.mkv -filter:a "atempo=2.0" -vn output.mkv

Using CUDA

Full hardware transcode with NVDEC and NVENC:

ffmpeg -hwaccel cuda -hwaccel_output_format cuda -i input -c:v h264_nvenc -preset slow output

ffmpeg was compiled with support for libnpp, it can be used to insert a GPU based scaler into the chain:

ffmpeg -hwaccel_device 0 -hwaccel cuda -i input -vf scale_npp=-1:720 -c:v h264_nvenc -preset slow output.mkv

The -hwaccel_device option can be used to specify the GPU to be used by the hwaccel in ffmpeg.

FHD 1080p 60FPS Dolby Digital 5.1 -Setting

@echo off

echo "Using CUDA to enhance FHD1080p with 60 FPS and Dolby Digital 5.1"
set input=%1
set output=%2
set def="1080p F60 5.1"

ffmpeg -hwaccel_device 0 -hwaccel cuda -i "%input%" -vf scale=-1:1080 -r 60 -c:v hevc_nvenc -preset slow -ac 6 -map 0 -c:a ac3 "FHD_60FPS_DolbyDigital_%output%"

Audio

Individual channels:

Standard channel layouts:

upmix to 5.1

ffmpeg -i input.mkv -filter_complex "[0:a]pan=5.1(side)|FL=FL|FR=FR|LFE<FL+FR|SL=FL|SR=FR[a]" -map 0 -map -0:a -map "[a]" -c copy -c:a flac output.mkv

ffmpeg -i "${INPUT}" -filter_complex "[0:a]pan=5.1(side)|FL = FL|FR = FR|FC < 0.5*FL + 0.5*FR|LFE < FL+FR|SL = FL|SR = FR[a]" -map 0 -map -0:a -map "[a]" -c copy -c:a ac3 "${OUTPUT}"

ffmpeg -i input.mkv -filter_complex "[0:a]pan=5.1(side)|FL=FL|FR=FR|LFE<FL+FR|SL=FL|SR=FR[a]" -map 0 -map -0:a -map "[a]" -c copy -c:a eac3 output.mkv

upmix to 6.1

ffmpeg -i input.mkv -filter_complex "[0:a]pan=6.1(side)|FL=FL|FR=FR|LFE<FL+FR|SL=FL|SR=FR|FC<FL*0.5+FR*0.5" -map 0 -map -0:a -map "[a]" -c copy -c:a flac output.mkv